Zhou, Leilei, Zengqiang Chen, Jiezhi Wang, and Qing Zhang. 2017. “Ultimate Boundary Estimations and Topological Horseshoe Analysis of a New 4D Hyper-Chaotic System”. Nonlinear Analysis: Modelling and Control 22 (5): 579-97. https://doi.org/10.15388/NA.2017.5.1.